The present invention relates to product packages and, more particularly, to methods of forming a rigid package having a recloseable locking mechanism so as to allow the removal of consumable products, such as candy items, from the package.
In the packaging of various consumable products, such as candy items and the like, various package constructions have been proposed. For example, in the case of mints, which can be shaped as pills or tablets, various rigid and soft packages have been created that allow the opening and reclosing of the package so that the consumer can open and reclose the package to consume mints only when desired. Such packages include paper or foil rolls, tin cans having openable and closable lids and rigid plastic containers having hinged flaps that are molded to allow the flap to lock or snap shut when the package is closed.
One type of package that has proven to be popular is a xe2x80x9ccredit cardxe2x80x9d type package for packaging small pill-shaped mints. These packages are formed of two injection molded halves of polystyrene or polypropylene snapped together to define a cavity for the mints. The two halves have plan dimensions that are approximately the same as conventional credit cards although when snapped together with mints therebetween, the package is somewhat thicker than a conventional credit card. Thus, the two halves are generally flat and when combined define a seam extending around the peripheral edge of the package. At one corner of one of the halves a hinge is provided so that a corner portion can be bent back and mints can be released from the package through the opening formed by the corner portion. The corner portion is provided with a recess on an inner surface that mates with a corresponding projection on the other half of the package. Accordingly, when closed, the recess of the corner portion interlocks with the projection of the opposing half to prevent inadvertent opening of the package, such as may occur with other package types when placed in a purse or pocket of the consumer. The credit card-type packages can hold, for example, 50 mints and can be opened and closed a corresponding number of times to allow dispensing of individual mints.
When packaged by the manufacturer, the credit card-type packages are overwrapped with a plastic film wrapper, such as a polyester, polypropylene or cellophane film. The film wrapper serves two purposes. First, the film wrapper provides a moisture barrier to prevent moisture from contaminating the mints packaged therein. Although fitting together closely, the two molded halves of the package do not by themselves form a hermetic seal. Accordingly, the film wrapper provides a moisture barrier which prevents moisture, such as humidity in tropical climates, from permeating to the mints during shipping and while stored or displayed at the point of purchase. The consumer first peels away the film wrapper, which may be provided with a tear strip, and then bends back the corner portion of one of the molded halves of the package.
A second purpose of the plastic wrapper is to provide tamper-evident protection. To prevent tampering with the mints during the shipping, storage and display stages of the retail process, the film wrapper provides visible evidence in the event an attempt is made to tamper with the product. The consumer can easily determine whether the package has been previously opened, or an attempt has been made to open the package, by visually inspecting the integrity of the film wrapper.
Conventional credit card-type packages have several disadvantages. First, the injection molding process for forming the halves of the package is relatively expensive and involves the tooling costs and cycle times associated with injection molding processes. In addition, the halves are often assembled by hand which entails the attendant labor costs and assembly times normally associated with manual labor.
Another manufacturing technique that has been used in connection with other packages, such as blister packages for pharmaceuticals, involves thermoforming a thermoplastic web of material into a desired shape. A generally flat web of material is advanced through a thermoforming station which is provided with opposed dies having corresponding projections and depressions. The dies are closed and heat and pressure are applied to the web of material to plastically deform the material into the desired shape. Upon cooling, at least part of a package is formed, such as the blister portion of a conventional blister package. A foil lidstock is often then heat sealed to the blister portion to seal the package closed. The thermoforming process is relatively inexpensive and can provide high throughput.
However, one disadvantage of thermoformed packages is that the packages generally cannot be opened and reclosed such that the package is locked when reclosed. For example, once the foil lidstock has been peeled back, it typically cannot be securely reclosed. Accordingly, there is a need in the industry for a package which achieves the benefits of thermoforming processes, namely lower cost and higher processing speeds, while at the same time providing the recloseable features of conventional injection molded packages wherein certain edges and surfaces of the molded pieces can be shaped to interlock when the package is closed.
A further disadvantage of conventional credit card-type packages is the need to overwrap the package with a plastic wrapper. The wrapping of these packages involves an extra processing step during manufacture and also requires a corresponding unwrapping step on behalf of the consumer. Accordingly, it would be advantageous to provide a credit card type-package that retains both the moisture barrier and tamper-evident properties of conventional credit card-type packages but yet which does not require a separate plastic wrapper around the package.
All of these desirable attributes are advantageously provided by the present invention as discussed further below.
The above and other needs are met by the present invention which, in one embodiment, provides a method of forming a thermoformed recloseable flat package for a pill-like product. A first enclosure portion having a closing member is first operably engaged with a second enclosure portion so as to form an enclosure for containing the product therein. Each enclosure portion has a major surface such that the major surfaces of the respective enclosure portions are generally parallel when the first and second enclosure portions are operably engaged. A component of a locking mechanism is then formed, following formation of the enclosure. The locking mechanism generally comprises a first component operably engaging the closing member and a second component operably engaging the second enclosure portion. The first component corresponds to, and is configured to operably engage, the second component to secure the closing member to the second enclosure portion. The components of the locking mechanism are further configured to be separable so as to allow separation thereabout of the closing member from the second enclosure portion. A recloseable package capable of selectively allowing the product to be extracted from the enclosure is thereby defined.
Another advantageous aspect of the present invention comprises a method of forming a thermoformed recloseable flat package for a pill-like product, wherein a first enclosure portion having a closing member is first operably engaged with a second enclosure portion defining at least one aperture component of a locking mechanism so as to form an enclosure for containing the product therein. Each enclosure portion has a major surface such that the major surfaces of the respective enclosure portions are generally parallel when the first and second enclosure portions are operably engaged. A projection component of the locking mechanism is then formed from the closing member, following formation of the enclosure. The projection component corresponds to, and is configured to operably engage, the at least one aperture component to secure the closing member to the second enclosure portion. The components of the locking mechanism are further configured to be separable so as to allow separation thereabout of the closing member from the second enclosure portion.
Still another advantageous aspect of the present invention comprises a method of forming a thermoformed recloseable flat package for a pill-like product, wherein a first enclosure portion having a pivotable closing member is first operably engaged with a second enclosure portion defining at least one lip component of a locking mechanism so as to form an enclosure for containing the product therein. Each enclosure portion has a major surface such that the major surfaces of the respective enclosure portions are generally parallel when the first and second enclosure portions are operably engaged. A projection component of the locking mechanism is then formed from the closing member, following formation of the enclosure. The projection component corresponds to, and is configured to operably engage, the at least one lip component in an interference fit, with respect to pivoting of the closing member, to secure the closing member to the second enclosure portion. The projection component is further configured to be separable from the at least one lip component so as to allow separation thereabout of the closing member from the second package portion.
Yet another advantageous aspect of the present invention comprises a method of forming a thermoformed recloseable flat package for a pill-like product, wherein a first package portion having a pivotable closing member is first operably engaged with a peripheral flange of a second package portion so as to form an enclosure for containing the product therein. Each enclosure portion has a major surface such that the major surfaces of the respective enclosure portions are generally parallel when the first and second enclosure portions are operably engaged. A portion of the peripheral flange corresponding to the closing member is then undercut so as to form opposing first and second components of a locking mechanism. The components of the locking mechanism are operably engageable and configured in an interference fit, with respect to pivoting of the closing member, to secure the closing member to the second enclosure portion. The first and second components are further configured to be separable to as to allow separation thereabout of the closing member from the second enclosure portion.
Thus, embodiments of the present invention provide methods of forming a recloseable package for a product which achieve the benefits of thermoforming processes, namely lower cost and higher processing speeds, while at the same time provide the recloseable features of conventional injection molded packages wherein certain edges and surfaces of the molded pieces can be shaped to interlock when the package is closed. By forming the locking mechanism after assembly of the package, a high correspondence between the components of the locking mechanism may also be achieved.